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Synthesis and Crystal Structure of Tris(4-nitrophenyl isocyanide)bis(diethyl phenylphosphonite)cobalt(I) Perchlorate
No full textThe syntheses of five-coordinate cobalt(I) complexes of the type [Co(4-NO2C6H4NC)5-x(PhP(OEt)2)x]ClO4 (x = 2 or 3) obtained by reaction at room temperature of 4-nitrophenyl isocyanide with cobalt(II) chloride and diethyl phenylphosphonite is reported. The compounds were characterized on the basis of their chemical and physical properties (conductivities and infrared, electronic, and 1H NMR spectra). The crystal and molecular structure of tris(4-nitrophenyl isocyanide)bis(diethyl phenylphosphonite)cobalt(I) perchlorate, [Co(4-NO2C6H4NC)3(PhP(OEt)2)2]ClO4, has been determined by single-crystal x-ray analysis and refined, with full-matrix least squares using anisotropic temperature parameters for all atoms, to R = 0.072 on F2. The crystals are monoclinic, space group P21/c (C2h5), with a = 13.085 (5) Å, b = 10.826 (4) Å, c = 33.019 (8) Å, β = 91.92 (3)°, and Z = 4. The coordinated polyhedron around the cobalt atom has the shape of a slightly distorted trigonal bipyramid with isocyanide ligands in the equatorial positions. The average Co-C and Co-P distances (1.80 and 2.175 Å, respectively) clearly indicate strong double-bond character. Distortions around the phosphorus atoms are compared with those found in Ni(II) and Fe(II) complexes with the same phosphonite ligand and correlated to the M-P ir interaction. © 1976, American Chemical Society. All rights reserved
Crystal structure of the complex of palladium with biacetyl-bis(N-methyl,N-phenyl)osazone
No full textIn the title compound, the biacetyl bis-(N-methyl,N-phenyl)osazone acts as a tridentate ligand, the nitrogen atoms bonding via the lone pairs
Trinitrato-(O,O')(triethylene glycol)europium(III), Eu(NO3)3 (C6H14O4).
Get PDFThe title compd. is monoclinic, space group P21/c, with a 12.342(5), b 9.305(4), c 14.201(5) Å, and β 110.88(5)°; dm = 2.12(1) and dc = 2.13 for Z = 4. The final R = 3.16% for 2286 reflections. The Eu is 10-coordinated, being directly bonded to the O atoms of the glycol and of 3 bidentate NO3. The glycol mol. forms a ring-like structure around the metal together with a NO3 ion; 2 other NO3 are axial above and below the ring plane. Eu-O bond distances are 2.433(4)-2.508(4) Å for the glycol and 2.488(5)-2.522(5) Å for the NO3 atoms. At. coordinates are given.
= 1 5 2 4 ( l ) A r . Z=4. D - ( f l o t a t i o n ) - 2 . t 2 i l ) , . ' ,
=2 l 3 M c m - r , M o K u , 1 : 0 . 7 t 0 6 9 4 " u :
4.55 mn-', F(om)- 952, rmm temFrarure. À =
3.16% Íor 2286 obsened .enections. The Eu atom ìs
@n-c6rdinated being diredly bonded to rhe oxygen
aroms of the gly@l Md of thrce bidetrtate nitrates. The
glycol molecule forms a ringlike strucrure around rhe
metd together with a nitrate iooi go orher nitrates are
uial above ùd below lhe ring plee. Eu-O bond
dstances are in rhe range 2.433 (4F2.508 (4) A for rhe
s.ly@l md 2.488 (5F2.522 (5) A for rh€ ntraro
oxyg€n abms
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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